No politically appointed official in U.S. history has played such a prominent role in killing so many people outside of a war zone as John Brennan. He has been a "close advisor" to President Barack Obama since November 2008, was a Team Lead for the president-elect’s review of the U.S. Intelligence Community (IC), and has served as homeland security advisor and deputy national security advisor for counterterrorism, with the rank of assistant to the president, since the first day Obama entered office. Brennan does not merely fill a White House position, but also meets with the president several times a day and — according to administration officials — serves as "a priest whose blessing has become indispensable to Obama."

Brennan plays the essential role in shaping and implementing Obama’s vision for protecting the United States, its allies, and its interests from politically motivated violence. The predominant counterterrorism tool under Obama has been targeted killings in non-battlefield settings, and Brennan reportedly oversees and manages the 100-person inter-agency process that nominates and vets suspected militants and terrorists for the United States’ variouskill lists — implemented by the CIA and Joint Special Operations Command. Obama’s has been a "lethal presidency," and Brennan is the Lethal Bureaucrat. Despite his close relationship to Obama and preeminent duty in coordinating the kill lists, he flies largely under the mainstream media’s radar.

First, it is important to understand the scope of what Obama has authorized in comparison with his predecessor. Since Sept. 11, 2001, there have been an estimated 393 targeted killings — in Yemen, Pakistan, Somalia, and the Philippines. (President George W. Bush also authorized an October 2008 raid six miles inside Syria to kill Abu Ghadiyah, an Iraqi-born senior operative of Al Qaeda in Iraq, as well as several of his bodyguards and several civilians.) Under Bush, there were roughly 50 targeted killings; under Obama there have been 343 in less than half the time — 95 percent of them by Predator or Reaper drones. At least 2,000 people have been killed by U.S. targeted killings since Obama entered office.

Brennan is especially well-suited for his position at the intersection of lethal covert operations and bureaucratic management. He spent a quarter-century in the IC, serving in wide-range of distinguished roles, including as Middle East chief of station, daily intelligence briefer for President Bill Clinton, and — from 1999 through 2005 — chief of staff to CIA Director George Tenet, deputy executive director of the CIA, and head of the Terrorist Threat Integration Center, later named the National Counterterrorism Center. It was during these years that Bush authorized the CIA to use enhanced interrogation techniques (i.e., torture) by its agents, and transferred hundreds of people into the extraordinary rendition program where many were tortured by foreign intelligence agencies.

In 2005, Brennan retired — as he claimed — "to lead and shape the future direction of The Analysis Corp (TAC)," an intelligence consulting firm where he was president and CEO. While running TAC, according to a corporate press release: "Brennan leveraged his knowledge of intelligence matters and his expertise on terrorism and security issues to guide the company’s rapid corporate growth and innovative business strategy." During this time Brennan also appeared on TV to discuss the Bush administration’s controversial counterterrorism policies. In 2005, on PBS’ Newshour he described extraordinary rendition as "an absolutely vital tool," which "without a doubt has been very successful as far as producing intelligence that has saved lives." In 2007, he told CBS News that waterboarding was "the classic definition of torture," which is "inconsistent with American values and it’s something that should be prohibited."

In 2007, Brennan also became a foreign-policy adviser to the Obama presidential campaign, though he never met Obama until the president-elect summoned him to Chicago just after the election in November 2008. Upon meeting, as Daniel Klaidman writes: "Their views were so complementary that Obama found himself finishing Brennan’s sentences." In this campaign role, Brennan gave interviews to tout Obama’s IC priorities, noting that Obama believed that covert action "cannot be done by a single branch of government," with oversight by both Congress and the courts a must for such activities. Brennan’s rumored nomination to become CIA Director was resisted by progressives and psychologists, who sought a clean break from Bush’s global war on terror approach. Brennan withdrew from consideration for the position in a Nov. 25, 2008, letter to Obama, complaining that, "The fact that I was not involved in the decision-making process for any of these controversial policies and actions has been ignored."

Today, nobody could say Brennan is not intimately and directly involved in the decision-making process for who America kills. According to Klaidman, he chairs the weekly "Terror Tuesday" inter-agency meetings, where national security threats are discussed and terrorist operatives are considered for adding to the kill lists. New York Times reporter David Sanger revealed earlier this year that Brennan has "pressed the case for the judicious use of drones…. His view carried considerable weight, because it was often Brennan who made the final call on authorizing specific drone strikes, from his cramped office in the basement of the West Wing." Finally, Associated Press reporter Kimberly Dozier reported a blockbuster story in May about how targeted killings were further concentrated under Brennan’s watch:

John Brennan has seized the lead in guiding the debate on which terror leaders will be targeted for drone attacks or raids, establishing a new procedure to vet both military and CIA targets. The move concentrates power over the use of lethal U.S. force outside war zones at the White House….

The move gives Brennan greater input earlier in the process, before senior officials make the final recommendation to President Barack Obama. Officials outside the White House expressed concern that drawing more of the decision-making process to Brennan’s office could turn it into a pseudo military headquarters, entrusting the fate of al-Qaida targets to a small number of senior officials…(S)ome of the officials carrying out the policy are equally leery of "how easy it has become to kill someone," one said.

It should be noted that all of the powers endowed within Brennan’s cramped White House office were bestowed by Obama, who, as commander-in-chief, has shown unmatched enthusiasm for "broadening the aperture" of whom the United States will use lethal force against. Although both Clinton and Bush had their own under-reported kill lists, neither was nearly as willing to attempt to kill as many named and anonymous suspected militants or terrorists — as well as innocent civilians. This is primarily due to the distinct capabilities that drones provide compared to other military tools to reduce many of the inherent political, diplomatic, and military risks of targeted killings. (Obama has roughly three times the number of armed drones Bush did.) Brennan has touted drones’ "surgical precision, the ability, with laser-like focus, to eliminate the cancerous tumor called an al-Qaeda terrorist while limiting damage to the tissue around it." He also used this cancer metaphor at his first meeting with Obama, when they were finishing each other’s sentences.

What is unique about Brennan’s unprecedented role — as compared to previous White House counterterrorism advisers, such as Richard Clarke and Frances Fragos Townsend — is his responsibility in directing and implementing the vast targeted killing program that Obama has authorized. (It’s also noteworthy that Brennan reportedly opposes the death penalty, presumably within the United States.) Despite Obama conducting nearly seven times the number of targeted killings than his predecessor, the administration has never provided a clear articulation of its policies and processes, nor answered challenging questions, such as whether legitimate targets include children, individuals attempting to rescue drone strike victims, and the funeral processions of deceased militants; each of these categories has been targeted by the United States on multiple occasions. The people killed in such lethal operations, were all the victims of signature strikes, which, when asked, Brennan refused to acknowledge even occur. Moreover, as an executive branch appointee, he is not the "lead executive authority" for drone strikes — either the CIA director or the secretary of defense — and will never be required to answer a congressional subpoena to explain the logic of signature strikes, or any aspect of his job.

In a 2006 interview, a then-retired Brennan offered some thoughtful comments about how to balance terrorist threats with American values:

It’s a tough ethical question, and it’s a question that really needs to be aired more publicly. The issue of the reported domestic spying — these are very healthy debates that need to take place. They can’t be stifled, because I think that we as a country and a society have to determine what is it we want to do, whether it be eavesdropping, whether it be taking actions against individuals who are either known or suspected to be terrorists. What length do we want to go to? What measures do we want to use? What tactics do we want to use?

Six years later, this sounds like an useful and long-overdue public debate worth having, and these would be excellent framing questions for President Obama’s targeted killings, and John Brennan’s role in seeing them to their execution.